Dog Nutrition: An In-depth Dive into Dog Nutritional Requirements

21 Minute Read
Updated February 27, 2021

Do you know what your dog's body needs to thrive? Your dog's nutrition is the foundation of their health, so let's take a look at what they need so you can find a diet that supports them.

From how they are built to what they eat, your dog has unique qualities and functions that can only be nourished with the right nutrition. To find the best diet for your dog, you need to understand what your dog needs to stay healthy and active. What do dogs need in their diet? or What nutrients do dogs need?

Every Dog is Different

Like our own diets, your dog's nutritional needs aren't always black and white - the same goes for your dog's energy requirements. From body weight to breed, different dogs require different nourishment. There are many differing opinions when it comes to nutrition. To make matters worse, businesses are better than ever at playing off of our emotions and common misconceptions about our pets to convince us to buy their product.

With so many different feeding options out there, how could you possibly know which one is the right food for your dog? Before we can dive into helping you find the right food, it will help to understand how your dog’s body works and what nutrients are necessary for them to thrive. 

In this article, we take a very hard look at your dogs nutritional needs. This is a great starting point as you try to determine the best food for your dog. Since this article is so in-depth, here is a table of contents to help you navigate

Are Dogs Carnivores?

dog food requirements

What is a Carnivore?

Not all carnivores are the same, and dogs fall into a unique category of carnivores. 

Wait, what!?!    Yep, I said dogs are carnivores. 

A carnivore is defined as an animal whose nutritional requirements cannot be met with plant protein alone. This means that they need a primarily meat-based diet to survive.

When we talk about carnivores, the definition above is what comes to mind, right? To be more specific, that definition is referring to an obligate carnivore. Obligate carnivores, like cats, would struggle to survive without animal protein in their diet. 

Dog’s are not obligate carnivores. The more appropriate classification for dogs is a scavenging carnivore. Generally, a scavenger is an animal that eats mostly dead things. They feed on leftover carcasses and fallen plants.

They play an important role in the animal kingdom as they eat the leftovers of other animals. This doesn't mean that they can't or don't hunt live prey too. Live prey is, more often than not, in short supply in the wild, so scavenging for whatever meat sources are available is how many wild dogs and other scavenging animals have survived. 

In the wild, dogs eat whatever food sources they can find. When food is scarce, animal protein may not be easily available for days, or even weeks at a time. They must be able to survive on a meatless diet, but will naturally gravitate towards animal protein when it is available. 

It begs the question though, just because they can, does that mean they should?

Evidence of Carnivorous Tendencies in Dogs

When we assess your dog’s physical characteristics, it’s obvious that they show many carnivorous traits. From teeth to tails, dogs are built like carnivores, despite their herbivorous abilities.

Let’s take a look at some of the traits that scream carnivore. This will help you understand why we consider dogs scavenging carnivores and why a meat-based diet will benefit your dog’s health. 


All plants have an outer casing made of cellulose, which is an indigestible fibre. For any of the nutrients from the plant to be digested, the cellulose casing needs to be removed. Omnivores and herbivores use their flat molars to grind the plant material, making the plant nutrients accessible and easy to digest. 

Unlike an omnivore, your dog is equipped with sharp, serrated molars and a wide-set jaw that moves vertically to slice meat like scissors. This allows them to swallow large chunks of soft tissue. 

Without flat molars, dogs do not have the ability to grind their plant material. In the wild, eating a plant-based diet would offer fewer digestible nutrients than a meat-based diet. 

It may not affect their ability to eat modern dog food, but it does point out an obviously carnivorous trait. 


The pancreas is an important part of the digestive system. It is responsible for producing digestive enzymes that break down fats, proteins, and carbohydrates. 

This organ is not specifically a carnivore trait, but in dogs, it is designed to most efficiently break down animal protein and fat. 

For omnivores and herbivores, carbohydrate digestion starts in the mouth, where the digestive enzyme Amylase is secreted in their saliva. The function of this enzyme is to break down carbohydrates. 

Dogs do not have this omnivorous ability, and carbohydrate digestion happens only in the small intestine, like a carnivore. Dogs are able to digest carbohydrates, but there may not be enough of the carb-eating enzyme to process the high carbohydrate content of many commercial diets, like kibble. 

Stomach and Small Intestine

Dogs are capable of processing food quicker than typical omnivores. This is thanks to their large stomach capacity and short digestive tract. 

Food spends more time in their stomach, soaking in the naturally acidic environment. That long acid bath is what allows them to break down protein, fats, and even bone. 

Most importantly it helps to prevent harmful bacteria from spreading, like bacteria present on raw meat. Preventing harmful bacteria from spreading is something that omnivores like us can not do.

To learn more about your dog's body breaks down food, check out The Dog Digestive System: A Beginners Guide to your Dog's Anatomy.

Omnivorous Ability of Dogs

Although dogs have a carnivorously geared digestive system, they are capable of digesting plant matter better than obligate carnivores. In modern dog diets, the ingredients are all ground and mixed, so they don’t have to struggle with the cellulose casing that you’d see on unprocessed plant material. 

Dogs can even survive on completely plant-based diets if that’s what you choose to feed. I’m sure you’ve noticed the rise in vegetarian and vegan dog foods hitting the market over the last 5-10 years. 

Nutrients from plants may not be as plentiful as those from animal sources, but with carefully chosen ingredients and the right supplementation, a plant-based diet can provide dogs with the basics of what they need to live. 

That being said, diets that include animal protein will provide nutrients that are easier to digest. Most commercial pet foods use protein from both plant and animal sources which can offer a wider variety of nutrients. 

This is the difference between food that helps your dog survive versus food that allows them to thrive.

Macronutrients for Dogs

Now that you know how your dog is designed to eat, let’s talk about the different nutrients that their bodies need and where to get them. These are two terms that we used to help categorize different types of nutrients required in your dog’s diet.

  • Macronutrients are the structural components of dog food: protein, carbs, and fat. Each of these is digested differently and used to supply energy and nutrition to every part of their body.

  • Micronutrients are the nutrients that the body gets from digesting macronutrients. Vitamins, minerals, and amino acids are all micronutrients.

Macronutrients are the foundation of your dog’s diet so they will be the focus of this article. Understanding what they do and why your dog needs them will help you assess their food and make the most beneficial and nutritious diet choices for them. Whether you are dealing with a large breed

To learn about essential micronutrients in your dog's food, check out How to Read & Understand Pet Food Labels.



dog nutrition

What is a protein used for? Everything! Protein plays a role in literally every part of your dog’s body.

It provides energy used for building and maintaining muscle mass, and supports all systems of the body, like skeletal structure, cell growth, and even helps to regulate pH balance in the body.

All enzymes are made up of proteins too, so proteins are essential to your dog's immune system and hormone production. 

To help you better understand why proteins are such an integral part of your dog's health, let's break apart protein, literally, to find out what exactly it provides and how your dog's body uses them. 

Amino Acids

When proteins are digested, they break down into amino acids. Amino acids are the most important micronutrients in your dog's diet. They are used to build new proteins, such as the proteins that make up hormones, muscles, and even cells. 

Dogs are able to synthesize some amino acids on their own, but there are 10 amino acids that they can’t make. They are called essential amino acids, meaning they must be obtained through diet. Without them, many systems in your dog’s body that rely on those amino acids will not function properly. 

Animal proteins are complete, meaning they contain all 10 of the essential amino acids and even some non-essential ones. Essential amino acids can be found in plant protein as well, but only a small number of plant proteins contain all 10. 

Here’s a chart outlining the benefits of each essential amino acid for dogs, and one bonus amino acid:

Amino Acid Purpose
Arginine Important for blood vessel dilation and improved circulation
Histidine Maintains hemoglobin, improving oxygen circulation to the whole body
Methionine Aids in keratin synthesis to promote healthy skin and coat
Threonine Plays a role in energy production 
Isoleucine Involved in healthy muscle development and protein synthesis
Leucine In healthy muscle development and protein synthesis
Valine In healthy muscle development and protein synthesis
Phenylalanine Required for thyroid and adrenal gland function
Lysine Aids in protein synthesis for growth and development
Tryptophan Necessary for hormone production like serotonin and melatonin

Sources of Amino Acids

Amino acids are found in all proteins, with the highest concentration and variety from animal protein.

Animal protein provides a complete spectrum of essential amino acids, all of which are required to maintain and support all of the body’s functions. They are a chain, so when one of them is missing the rest can’t perform adequately. One such requirement you are likely familiar with is omega-3 fatty acids.

Although plants do provide digestible protein usable for energy, plant sources lack high enough levels of many of the essential amino acids required in your dog’s diet. This is why we recommend that a large portion of the protein that your dog consumes is sourced from an animal. 

Many brands use plants to increase their food’s protein content and give consumers the perception of high quality and high animal inclusion. Be cautious of where your macronutrients are coming from. 

dogs nutritional needs

Biological Value

Bioavailability is a term used to describe the ability of a nutrient to be absorbed by a living organism. The term bioavailability is commonly used to indicate the quality of a macronutrient.

Meat often has a higher biological value than most grains, furthering the argument that dogs are carnivorous in nature. 

For example, eggs have a very high biological value, meaning that they are easy to digest and the nutrients and benefits of eggs are easily absorbed and utilized by the body. 

Although they are generally not the main source of protein, eggs are often added to boost the bioavailability of the dry food and ensure that your dog is receiving the appropriate quantity and balance of amino acids, energy, minerals, and vitamins.



Next, let’s talk about carbohydrates. Carbohydrates can provide many essential nutrients but are often over or inappropriately used in modern pet foods. All carbs are not created equally, and finding the right dry food for your dog or cat means looking for the right types and quantities of carbohydrates.

Some carbs are better for your dog or cat than others. Let’s break down the four types of carbohydrates so that you can see how some carbs are better than others.

1. Absorbable 

nutritional needs of a dog

Absorbable carbohydrates are a quick energy source. Your dog or cat will use these to metabolize and digest their food, as well as supply energy to various systems of the body. Absorbable carbs have a rapid effect on blood sugar levels, so too many absorbable carbs in their diet can lead to unused energy that needs to be stored. 

Sugar is a good example of an absorbable carbohydrate. You won’t see sugar in the ingredients of any good quality foods, but you may see things like honey, molasses, caramel, and beet pulp. 

Excessive sugars in your dog’s diet can contribute to digestive issues. The sugars feed bacteria, good and bad. Limit the amount of this type of carb to reduce unnecessary weight gain, excess sugars, or unused energy. 

2. Digestible

nutrition requirements for dogs

Digestible carbohydrates, or starches as we know them, take a little longer to digest. Enzymes in the small intestine are needed to break down starches into an absorbable format. Starches are used for energy just like absorbable carbs are. 

Starches found in pet food include potatoes, rice, wheat, or corn. Starches take slightly longer to digest, but can still have a significant effect on blood sugar if overfed. 

Dogs, lacking the amylase enzyme in their saliva, have a harder time digesting starches than an omnivore would so feed these in moderation. 

3. Fermentable

Fermentable carbohydrates are used by the bacteria in your dog’s intestines as a source of food. These are known as prebiotics. They ferment during digestion, and produce sugars that are then used to feeding existing bacteria in their gut.

You will often find prebiotics in commercial dog foods in the form of alfalfa or chicory root. Fermentable carbs are a healthy carbohydrate source, but overfeeding prebiotics can still cause problems. 

Only certain types of bacteria can survive the acidic environment of your dog’s stomach, so supplementing healthy bacteria in their diet isn’t always effective. Instead, adding prebiotics to their food will help to replenish your dog’s natural levels of healthy bacteria and improve digestion. 

4. Non-Fermentable

dog food requirements

non-fermentable carbohydrates are strictly a source of fibre. Fibre does not break down into sugars or energy. Instead, it acts as a digestion regulator. Fibre is essential to healthy digestion, and should always be included in your dog’s diet. 

There are two types of non-fermentable fibre that your dog’s body needs to maintain healthy digestion: Soluble and insoluble. Soluble fibre attracts water, slows digestion, and contributes to a feeling of fullness. It can be found in foods like oatmeal and berries. 

Insoluble fibre adds bulk and speeds movement through the digestive system. Brown rice is a great source of insoluble fibre. 

One of the best sources of fibre to supplement your dog’s diet is pumpkin. Pumpkin is a source of both soluble and insoluble fibre so it can regulate the speed of digestion. This is why it can be used for both diarrhea and constipation relief. 

Digginn Your Dog

Simple Carbs vs. Complex Carbs

How quickly a carbohydrate digests can have some big impacts on the value of that carb and the nutrients it offers. They can be classified as either simple or complex. 

Simple carbs 

Often called simple sugars, simple carbs have less value in your dog’s diet than a complex carbohydrate does. It doesn't mean you can’t feed simple sugars, but they do not offer much nutrition apart from a quick energy source. Simple sugar is made of a single sugar molecule, like glucose or fructose. 

Complex carbs

Complex carbs take longer to digest and release sugar into the blood slower. They are typically made up of many sugar molecules that are linked together. Your dog’s body has to separate the molecules, which leads to a slower release into their blood.

Complex carbs may contain fibre and other nutrients, making them more nutritious to your dog. 

When choosing a dog food, opt for complex carbs over simple carbs, but remember that too many of either can still cause the food to be unhealthy. Foods should be rich in meat and fat and complemented with limited complex carbohydrates.

Effects of Carbohydrates on Blood Glucose Levels

The effect that food has on your dog’s blood sugar is called the glycemic effect. By studying the glycemic effect of specific ingredients in humans, scientists were able to create the glycemic index, which is a number system for rating ingredients. 

High-quality diets should primarily include carbohydrates that have a low GI (glycemic index) value. Foods considered high glycemic releases sugar into the bloodstream quickly, causing your dog’s blood sugar levels to spike up, and rapidly drop when the sugars are used or stored by their body.

Quick drops in blood sugar can contribute to a feeling of hunger and can lead to overeating and weight issues. To help your dog feel full after eating, and to help regulate weight, it’s best to avoid foods that use a lot of high glycemic ingredients. 

Wheat and corn are two common dog food ingredients that have a high glycemic rating. Peas and quinoa are both low glycemic and release sugars into the bloodstream at a steadier rate.

dog nutrition

When excess glucose enters the bloodstream, the pancreas is called upon to produce a hormone called insulin. Insulin stores blood sugar in liver cells for later use. As blood sugars levels are depleted, the pancreas produces a hormone called glucagon, which signals the release of blood sugar from the liver to be properly distributed throughout the body.

The glycemic index used for humans is different from levels determined for dogs. For example, potatoes have a human glycemic rating of 90; that’s very high, but also misleading. Potatoes are high glycemic for humans, but in dogs, they have a low glycemic rating of only 34.

More research and data are needed to give us a more accurate measure of glycemic values in dogs, so for now we work with the human glycemic index for most ingredients. Unfortunately, this means that trying to determine the glycemic values of your dog food ingredients is less of a science, and more of an educated guesstimate. 

The Glycemic Load

Your dog’s food is a mixture of different ingredients, in different quantities, with different glycemic values. When you put all of those values together, you get the total glycemic load of their diet.

Avoiding high glycemic ingredients, like wheat and corn, can help, but low glycemic ingredients used excessively can still have a negative effect on blood sugar.

A small amount of a high glycemic ingredient may end up having a lesser effect on your dog than a large portion of a low glycemic ingredient when weighed as part of the total food. 

Stick to low glycemic ingredients whenever possible, and make sure that all carbohydrates are fed in moderation. Foods with a high meat inclusion, high protein, and low carbohydrates are going to have a lesser effect on blood sugar levels than a carb-heavy diet. 

Fats and Oils

nutritional needs of a dog

We’ve been told for years that fat is bad; that fat makes us fat. It’s easy to jump to the conclusion that it could make our pets fat too! Of course, too much fat combined with low activity is a recipe for a pudgy pup, but the right kind of fat is extremely healthy. It fact, it’s downright necessary. 

There are two kinds of fat that our pets need: Facilitating fats and Functional fats.

Functional fat, monounsaturated or polyunsaturated, either plays an important role in the structural or functional process of cells or can support cell function.

Facilitating Fats, or saturated fat, is an easily digested, concentrated source of energy. Your dog also needs saturated fats to absorb fat-soluble vitamins in their food. Most of the fat in your dog’s food is designed to provide energy. 

Both facilitative and functional fats are needed to support your dog’s overall health. Like all nutrients, the quantity and quality must be taken into consideration.

Can dogs have too much fat?

You will often see facilitating fat fairly high up in the ingredient list. It could be a named animal fat, or even a plant oil, like canola oil. This fat provides easily usable energy to support activity and metabolism. 

Healthy dogs are capable of digesting high levels of facilitating fat in their diets, but just like carbs, the energy provided by fat must be used, or else your dog will start to pack on pounds.

Canine obesity, caused by excessive calories and low activity lifestyle, increases the chances of many weight and age-related conditions. Some can be painful and require life-long treatment while others can quickly become life-threatening.

Acute pancreatitis, for example, is the sudden inflammation of the pancreas and can be linked to obesity and poor diet. The pancreas, whose jobs include digestive enzyme production and blood sugar regulation, is a vital part of your dog’s body.

When inflammation in the pancreas occurs, the digestive enzymes it produces are forced out of the pancreas and into your dog’s abdominal cavity. Here, they get to work doing what they do best - digesting.

Since the only things in their abdomen are their own tissues, that’s what the enzymes digest. Essentially your dog’s body starts eating away at itself. It's very dangerous and could become quickly life-threatening if left untreated.

Fat is a required nutrient in your dog’s diet, and while fat should be fed in moderation, make sure that you don’t limit fat too much. We see this in cases of extreme weight loss, where very low-fat diets are fed. Cutting out fat means depriving your dog’s body of vital energy and nutrition.

Essential Fatty Acids

Fatty acids are a type of functional fat. This means that they are needed to support cells and systems in your dog’s body. Dogs are capable of making many omega fatty acids, but like amino acids, some types must be supplemented in their diet. These are called essential fatty acids.

There are five essential fatty acids. Fortunately, all of them have common dietary sources.


nutrition requirements for dogs

Eicosapentaenoic Acid and Docosahexaenoic Acid. Don’t worry about trying to pronounce these ones, they are commonly referred to as EPA and DHA, respectively, to save up all the headache. EPA and DHA are both Omega 3 Fatty Acids that are primarily sourced from fish and fish oils. They can also be found in some kelp and sea-grasses, but they are much more difficult to source and not commonly used in commercial pet food. 

Both essential fatty acids support the immune system and cell growth. In addition, EPA can reduce inflammation to support mobility, pain management, and skin and coat health. 

DHA is vital to both retinal and heart function and is an important nutrient during growth stages and pregnancy. Perhaps it's most important benefit is it's role in cognitive function. Dogs of all ages will benefit from this functional fat, but puppies and senior dog will benefit the most. 

Pet-Tek Salmon Oil

Alpha-Linolenic Acid

Another essential fatty acid from the Omega 3 family is Alpha-Linolenic Acid. This fatty acid can be found in animal and plant sources. Your dog’s body can use Alpha-Linolenic Acid to make EPA and DHA, but not very well. Less than 20% of the Alpha-Linolenic Acid is converted

The good news is even though ALA supplementation doesn’t lead to large amounts of EPA or DHA production, it does contribute to the overall total and increases a type of fat compound, called a prostaglandin, derived from EPA that helps to regulate inflammation.

Your dog’s food will probably list levels of omega fatty acids, but it won’t tell you which fatty acids are present in the food. If there are no fish oils or fish products in your dog’s food, then it would be smart to supplement their diet with fish oils.

Even if your dog’s food does contain fish, it’s impossible to know how many of the nutrients survived the cooking process. Supplementing fish oils, even just once per week, can have a huge impact on your dog’s health over time.

Linoleic Acid

dog food requirements

Linoleic Acid is an Omega 6 Fatty Acid that is most commonly found in plant oils such as safflower, flaxseed, and olive oil. The main functions of Linoleic Acids are to support skin and coat, bone density, and reproductive health. It can also be sourced from animal proteins like chicken and pork, but not as abundantly as in plant matter. 

Arachidonic Acid

A lesser-known, but incredibly vital, Omega 6 Fatty Acid is Arachidonic Acid. The main benefit of this omega 6 is its pro-inflammatory properties.

It may sound a bit crazy to want inflammation, but it’s very important to your pet's immune system and defensive capabilities. Without appropriate inflammation responses, your dog’s body is susceptible to pathogens, bacteria, and anything else that could attack their body.

Although its role is to promote inflammation, when supplemented properly with other fatty acids, Arachidonic Acid will help to regulate inflammation and support your dog’s immune system.

The Fatty Acid Balance

Essential fatty acids maintain the most vital systems in your dog's body, so it is incredibly important that they are being provided in your dog's diet. Each essential fatty acid has its own unique benefits, but they work best when used together.

The ideal ratio of omega 3 to 6 fatty acids for dogs is 1:5-1:10. This allows each fatty acid to work the most efficiently. Although fatty acids are supplemented in most dog foods, the ratio isn’t always right for every dog. Dogs with allergies or skin issues can benefit from more Omega 3’s in their diet.

It's not just about the ratio either. Look at how much, where they are sourced from, and which EFA's are used. Fats and oils can come from poor sources, and quality affects how well your dog can use it.

When choosing a fish oil supplement, for example, stick to smaller wild-caught fish and rotate your fish oils with plant oils. Smaller fish will not have as much mercury build up in their system due to their position in the fish food chain, and offering plant oils can ensure a good mix of functional fats. 

Apply Your New Knowledge

dog nutrition

Now that you know your dog's basic dietary needs, it's time to take a look at their diet and their overall health. If you are concerned that your dog isn't as healthy as they should be, then you may need to consider that their staple diet may be missing a key component.

Every pet is different and what may work for one dog, may not be sufficient for another. 

Catering to both carnivorous and omnivorous traits makes canine nutrition very dynamic. There isn't going to be a one-size-fits-all option, regardless of what dog food companies advertise. Instead, you can try different diets with unique features and benefits to find the food that helps your dog thrive.

Check out our Dog Food Guide for more help finding the right food for your pet. 

Supplementation can also be helpful, particularly with fibre, omega fatty acids and digestive enzymes. Some dogs need more of these than others and they aren't always available in abundant enough quantities through their diet.

So go ahead and try out something new. You may be surprised by the difference an appropriately balanced diet and proper nutritional supplements can yield.

Written by

Krystn Janisse

Krystn is a passionate pet nutrition enthusiast. She has worked in the pet industry for over a decade and loves to share her passion for animal welfare with others. She loves all animals but is currently channeling some crazy cat lady vibes with her four lovable, but rebellious cats.


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